A5077436003- X-ray Spectroscopy and Fluorescence Analysis
- Advanced X-ray Imaging Techniques
- Electron and X-Ray Spectroscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Medical Imaging Techniques and Applications
- Nuclear Physics and Applications
- X-ray Diffraction in Crystallography
- Catalytic C–H Functionalization Methods
- CO2 Reduction Techniques and Catalysts
- Crystallography and Radiation Phenomena
- Atomic and Molecular Physics
- Photosynthetic Processes and Mechanisms
- Advanced Surface Polishing Techniques
- Spectroscopy and Quantum Chemical Studies
- Electrochemical Analysis and Applications
- Image Processing Techniques and Applications
- Radiation Detection and Scintillator Technologies
- Cultural Heritage Materials Analysis
- Radiation Shielding Materials Analysis
- Radical Photochemical Reactions
- Electrocatalysts for Energy Conversion
- Porphyrin and Phthalocyanine Chemistry
- Particle Detector Development and Performance
Technische Universität Berlin
2017-2024
Helmholtz-Zentrum Berlin für Materialien und Energie
2021-2024
Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy
2023
Instituto de Óptica "Daza de Valdés"
2018-2020
We have built a laboratory spectrometer for X-ray emission spectroscopy. The instrument is employed in catalysis research. key component von Hamos full cylinder optic with Highly Annealed Pyrolytic Graphite (HAPG) as dispersive element. With this very efficient optic, the subtends an effective solid angle of detection around 1 msr, allowing analysis dilute samples. resolving power approximately E/ΔE = 4000, energy range ∼2.3 keV-10 keV. and its characteristics are described herein. Further,...
Photoassisted catalysis using Ni complexes is an emerging field for cross-coupling reactions in organic synthesis. However, the mechanism by which light enables and enhances reactivity of these often remains elusive. Although optical techniques have been widely used to study ground excited states photocatalysts, they lack specificity interrogate electronic structural changes at specific atoms. Herein, we report metal-specific studies transient L- K-edge X-ray absorption spectroscopy a...
New developments in the description and modeling of Highly Annealed Pyrolytic Graphite (HAPG) mosaic crystals have led to possibility designing optimized optical solutions for X-ray absorption fine structure (XAFS) spectroscopy.
With time-resolved soft X-ray spectroscopy, the element-specific dynamics of electronic structure disordered systems can be investigated. Measurements species in dilute liquid solutions are particularly challenging and require high photon flux combined with low experimental noise. This mostly limited these experiments to large-scale facilities, especially for energies above water window (533 eV). Based on a laser-produced plasma source, our system enables, best knowledge, first static...
Calcium is an abundant, nontoxic metal that finds many roles in synthetic and biological systems including the oxygen-evolving complex (OEC) of photosystem II. Characterization methods for calcium centers, however, are underdeveloped compared to those available transition metals. Valence-to-core X-ray emission spectroscopy (VtC XES) selectively probes electronic structure element's chemical environment, providing insight complements geometric information from other techniques. Here, utility...
We analyze and compare 6 different approaches for evaluating energy position of single X-ray photons detected with conventional pixelated detectors.
This paper presents the development of a new reflection model for describing X-ray diffraction from mosaic crystals. In contrast to well established Zachariasen [Zachariasen (1994), Theory Diffraction in Crystals . Mineola: Dover Publications], it gives additional information on spatial behaviour and not just depth-integrated reflectivity crystal material. The enables concrete description performance an arbitrary spectrometer configuration. Multiple reflections inside are described by...
The extension of the pump-probe approach known from UV/VIS spectroscopy to very short wavelengths together with advanced simulation techniques allows a detailed analysis excited-state dynamics in organic molecules or biomolecular structures on nanosecond femtosecond time level. Optical pump soft X-ray probe is relatively new detect and characterize optically dark states molecules, exciton transient ligand-to-metal charge transfer states. In this paper, we describe two experimental setups for...
The combination of optimally adapted polycapillary lenses and highly brilliant liquid metal jet sources leads to significant enhancement in the sensitivity for transition metals using laboratory μXRF.
The presented scanning transmission x-ray microscope (STXM), build on top of our existing modular platform (FlexIX) for high resolution imaging experiments, allows versatile investigations different samples. FlexIX endstation to switch between a Full Field and STXM mode. For the mode we use spatialy resolved detector together with an energy dispersive detector, this investigate morphology chemical or elemental distribution sample simultaneous. combination nanoscopy XUV beamline P04 results...
A novel double full-cylinder crystal x-ray spectrometer for emission spectroscopy (XES) has been realized based on a modified von Hamos geometry. The is characterized by its compact dimensions, versatility with respect to the number of crystals used in series detection path, and option perform calibrated XES measurements. are highly annealed pyrolytic graphite thickness 40 μm, which was bent radius curvature 50 mm. flexible design allows an easy change-within same setup-between measurements...
We present a laser-driven, bright, and broadband (50 to 1500 eV) soft-x-ray plasma source with <10 ps pulse duration. This is employed in two complementary, laboratory-scale beamlines for time-resolved, magnetic resonant scattering spectroscopy, as well near-edge x-ray absorption fine-structure (NEXAFS) spectroscopy. In both beamlines, dedicated reflection zone plates (RZPs) are used single optical elements capture, disperse, focus the soft x rays, reaching resolving powers up E/ΔE > 1000,...
Ultrafast X-ray spectroscopy has been revolutionized in recent years due to the advent of fourth-generation facilities. In solid-state materials, core excitons determine energy and line shape absorption features core-level spectroscopies such as spectroscopy. The screening is an inherent many-body process that can reveal insight into charge-transfer excitations electronic correlations. Under non-equilibrium conditions after photoexcitation, however, core-exciton still not fully understood....
The presented scanning transmission X-ray microscope (STXM), built on top of a modular platform, combines soft and fluorescence microscopy with high detection efficiency spatial resolution. setups user concept as well the large solid angle (> 1 sr) integrated Silicon-drift-detector are unique characteristics this endstation. In combination beamline P04 at PETRA III (DESY), it delivers new type nanoscope, providing flexibility very low acquisition times.
Photo-assisted catalysis using Ni complexes is an emerging field for cross-coupling reactions in organic synthesis. However, the mechanism by which light enables and enhances reactivity of these often remains elusive. Although optical techniques have been widely used to study ground excited states photocatalysts, they lack specificity interrogate electronic structural changes at specific atoms. Herein we report metal-specific studies static transient L- K-edge X-ray absorption spectroscopy a...
Molecular systems can be used for a wide range of applications but complete description knowledge about their transient electronic properties is often required.Optical-pump soft X-ray-probe NEXAFS spectroscopy an ideal technique to investigate these due its elemental and orbital selectivity which allows probing the time evolution structure.Our laboratory spectrometer based on laser-produced plasma source covering energy between 200 -1500 eV with resolving power ≥1000 500 ps resolution.Due...
This paper presents a setup for the fast detection of soft x-rays using high speed camera as multimodal detector application in AnImaX scanning transmission x-ray microscope (STXM). is flexible endstation combining and full field microscopy XUV beamline P04 at PETRA III. While mode there additional option to gather fluorescence spectra each scanned pixel. Because brilliance beamline, image acquisition possible consequence demands efficient data management.